There is a current demand for cigarette tipping films which are transparent, allowing the smoker to view the effectiveness of the filter material enclosed within the tipping film.
Certain biodegradable substrates have been considered for use as cigarette tipping films. However, because of stringent demands in the tobacco industry with regard to the chemical make up of tipping films, and also with regard to their physical properties, there is a need to provide an improved form of tipping film which is substantially free from certain specified contaminants and which has excellent properties as far as elongation, tensile strength, shrinkage, flatness and tube/curl are concerned. In particular, the mechanical tolerances of any such film must be carefully controlled in order to allow the film satisfactorily to be deployed in the machinery used by the tobacco industry to wrap tipping papers around filter tips. Because of the relatively small size of the unit film, and the necessity for it to be tightly and neatly wound on the filter, it has proved difficult to develop a filmic material, particularly one with other desirable qualities such as biodegradability and transparency to meet these criteria.
The present invention seeks to address these issues.